package com.yupi.yuojcodesanbox;

import cn.hutool.core.io.FileUtil;
import cn.hutool.core.io.resource.ResourceUtil;
import cn.hutool.core.lang.UUID;
import cn.hutool.core.util.StrUtil;
import cn.hutool.dfa.FoundWord;
import cn.hutool.dfa.WordTree;
import com.yupi.yuojcodesanbox.model.ExecuteCodeRequest;
import com.yupi.yuojcodesanbox.model.ExecuteCodeResponse;
import com.yupi.yuojcodesanbox.model.ExecuteMessage;
import com.yupi.yuojcodesanbox.model.JudgeInfo;
import com.yupi.yuojcodesanbox.security.DenySecurityManager;
import com.yupi.yuojcodesanbox.utils.ProcessUtils;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class JavaNativeCodeSandbox implements CodeSandbox {
    private static final String GLOBAL_CODE_DIR_NAME="tmpCode";
    private static final String GLOBAL_JAVA_CLASS_NAME="Main.java";

    private static final long TIME_OUT = 5000L;

    private static final String SECURITY_MANAGER_PATH = "D:\\xingqiu\\yuoj\\yuoj-code-sanbox\\src\\main\\resources\\security";

    private static final String SECURITY_MANAGER_CLASS_NAME = "MySecurityManager";

    private static final List<String> blackList = Arrays.asList("Files", "exec");

    private static final WordTree WORD_TREE;

    static {
        // 初始化字典树
        WORD_TREE = new WordTree();
        WORD_TREE.addWords(blackList);
    }

    // 1.把用户的代码保存为文件
    // 2.编译代码，得到 class 文件
    // 3.执行代码，得到输出结果
    // 4.收集整理输出结果
    // 5.文件清理，释放空间
    // 6.错误处理，提升程序健壮性
    public static void main(String[] args) {
        JavaNativeCodeSandbox javaNativeCodeSandbox = new JavaNativeCodeSandbox();
        ExecuteCodeRequest executeCodeRequest=new ExecuteCodeRequest();
        executeCodeRequest.setInputList(Arrays.asList("1 2","3 4"));
        String code= ResourceUtil.readStr("testCode/Main.java", StandardCharsets.UTF_8);
//                String code = ResourceUtil.readStr("testCode/simpleComputeArgs/Main.java", StandardCharsets.UTF_8);
//        String code = ResourceUtil.readStr("unsafeCode/MemoryError.java", StandardCharsets.UTF_8);

        executeCodeRequest.setCode(code);
        executeCodeRequest.setLanguage("java");
        ExecuteCodeResponse executeCodeResponse=javaNativeCodeSandbox.executeCode(executeCodeRequest);
        System.out.println(executeCodeResponse);
    }
    @Override
    public ExecuteCodeResponse executeCode(ExecuteCodeRequest executeCodeRequest) {
//        System.setSecurityManager(new DenySecurityManager());

        List<String> inputList = executeCodeRequest.getInputList();
        String language = executeCodeRequest.getLanguage();
        String code = executeCodeRequest.getCode();
        //  校验代码中是否包含黑名单中的命令
//        FoundWord foundWord = WORD_TREE.matchWord(code);
//        if (foundWord != null) {
//            System.out.println("包含禁止词：" + foundWord.getFoundWord());
//            return null;
//        }

        //        1. 把用户的代码保存为文件
        String userDir=System.getProperty("user.dir");
        String globalCodePathName=userDir+ File.separator+GLOBAL_CODE_DIR_NAME;
        //判断全局代码文件目录是否存在
        if(FileUtil.exist(globalCodePathName)){
            FileUtil.mkdir(globalCodePathName);
        }
        //把用户的代码隔离存放
        String userCodeParentPath=globalCodePathName+File.separator+ UUID.randomUUID();
        String userCodePath=userCodeParentPath+File.separator+GLOBAL_JAVA_CLASS_NAME;
        File userCodeFile=FileUtil.writeString(code,userCodePath, StandardCharsets.UTF_8);
//        2. 编译代码，得到 class 文件
        String compileCmd = String.format("javac -encoding utf-8 %s", userCodeFile.getAbsolutePath());
        try {
            Process compileProcess = Runtime.getRuntime().exec(compileCmd);
            ExecuteMessage executeMessage = ProcessUtils.runProcessAndGetMessage(compileProcess, "编译");
            System.out.println(executeMessage);
        } catch (Exception e) {
            return getErrorResponse(e);
        }
        //3.执行代码，得到结果
        List<ExecuteMessage>executeMessageList=new ArrayList<>();
        for(String inputArgs:inputList){
//            String runCmd=String.format("java -Xmx256m -Dfile.encoding=UTF-8 -cp %s Main %s",userCodeParentPath,inputArgs);
            String runCmd = String.format("java -Xmx256m -Dfile.encoding=UTF-8 -cp %s;%s -Djava.security.manager=%s Main %s", userCodeParentPath, SECURITY_MANAGER_PATH, SECURITY_MANAGER_CLASS_NAME, inputArgs);
            try {
                Process runProcess=Runtime.getRuntime().exec(runCmd);
                // 超时控制
                new Thread(() -> {
                    try {
                        Thread.sleep(TIME_OUT);
                        System.out.println("超时了，中断");
                        runProcess.destroy();
                    } catch (InterruptedException e) {
                        throw new RuntimeException(e);
                    }
                }).start();
                ExecuteMessage executeMessage = ProcessUtils.runProcessAndGetMessage(runProcess, "运行");
//                ExecuteMessage executeMessage = ProcessUtils.runInteractProcessAndGetMessage(runProcess,inputArgs);
                System.out.println(executeMessage);
                executeMessageList.add(executeMessage);
            } catch (Exception e) {
                return getErrorResponse(e);
            }
        }
        //4.收集整理输出的结果
        ExecuteCodeResponse executeCodeResponse=new ExecuteCodeResponse();
        List<String> outputList=new ArrayList<>();
        //取最大值判断是否超时
        long maxTime=0;
        for(ExecuteMessage executeMessage:executeMessageList){
            String errorMessage=executeMessage.getErrorMessage();
            if(StrUtil.isNotBlank(errorMessage)){
                executeCodeResponse.setMessage(errorMessage);
                //用户提交代码执行中存在错误
                executeCodeResponse.setStatus(3);
                break;
            }
            outputList.add(executeMessage.getMessage());
            Long time=executeMessage.getTime();
            if(time!=null){
                maxTime=Math.max(maxTime,time);
            }
        }
        //正常运行完成
        if(outputList.size()==executeMessageList.size()){
            executeCodeResponse.setStatus(1);
            executeCodeResponse.setMessage("结果正确");
        }
        executeCodeResponse.setOutputList(outputList);
        JudgeInfo judgeInfo=new JudgeInfo();
        judgeInfo.setTime(maxTime);
        //要借助第三方库来获取内存，过于麻烦，不做展示
//        judgeInfo.setMemory();
        executeCodeResponse.setJudgeInfo(judgeInfo);
        //5.文件清理
        if(userCodeFile.getParentFile()!=null){
            boolean del=FileUtil.del(userCodeParentPath);
            System.out.println("删除"+(del?"成功":"失败"));
        }
        return executeCodeResponse;
    }


    /**
     * 获取错误响应
     * @param e
     * @return
     */
    private ExecuteCodeResponse getErrorResponse(Throwable e){
        ExecuteCodeResponse executeCodeResponse=new ExecuteCodeResponse();
        executeCodeResponse.setOutputList(new ArrayList<>());
        executeCodeResponse.setMessage(e.getMessage());
        //表示代码沙箱错误（可能是编译错误）
        executeCodeResponse.setStatus(2);
        executeCodeResponse.setJudgeInfo(new JudgeInfo());
        return executeCodeResponse;
    }
}